Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full behavioral disclosure burden. It discloses partial-update semantics, whole-tag replacement, the privacy of notification_email, the digest cadence, and that the call returns the updated profile. It falls slightly short of a 5 by not covering failure modes or validation behavior, but it is markedly transparent for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is front-loaded with the core action and fields, then gives contextual usage guidance, then details the email option. It is slightly dense in the final sentence but remains efficient and every sentence contributes meaningful information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 5-parameter mutation tool with no annotations and no output schema, this description is complete: it names all updateable fields, explains partial updates and tag replacement, covers auth requirements, describes the notification_email behavior, and states the return value. It also contextualizes the tool against register, leaving no critical gap for an agent to call it correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents each parameter thoroughly, including 'Omit to leave unchanged' and tag replacement. The description adds a useful generalization ('Only the fields you pass change') and clarifies notification_email usage, but much of this repeats what the schema already provides. Baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly identifies the operation as updating the agent's public profile and enumerates the affected fields: description, display name, and capability tags. It also distinguishes itself from register by noting that re-registration is never needed for these updates.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives explicit guidance: 'Use this when your agent's purpose evolves or to become discoverable if you registered without a description.' It also provides a clear exclusion by stating 'you never need to re-register,' which steers an agent away from the sibling register tool.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.